The Advantage of Magnetic Resonance Imaging in Diagnosis of Cauda Equina Syndrome in Dogs.

Abstract

ABSTRACT. Three dogs were evaluated in our study using magnetic resonance imaging (MRI) to reveal the anatomical deformity and the degree of the lesion of cauda equina. In all dogs, MRI revealed soft tissue, such as cauda equina, epidural fat, and intervertebral disc, at the lumbosacral region clearly without contrast medium. Our results suggest that MRI has some advantages in evaluating cauda equina syndrome in dogs. -KEY WORDS: canine, cauda equina syndrome, magnetic resonance imaging (MRI).J. Vet. Med. Sci. 60(12): 1345-1348, 1998 side of the L7-S1 disc space was appeared to encapsulate. The sagittal T2-weighted image (Fig. 1b) showed that the cauda equina at the lesion of L7-S1 was strongly compressed and the L7-S1 intervertebral disc was hypointense. We diagnosed this dog as discospondylitis which caused by B. canis at L7-S1 intervertebral disc space. Dog 2: This dog had a decreased tail tone, weakness of the hind limbs and excreted soft feces. Survey radiographs revealed that the ventral canal height was decreased at the level of L7-S1 lesion and the density of both L7 caudal and S1 cranial end-plates were increased (Fig. 2a). The sagittal T1-weighted image ( Fig. 2b) showed that the loss of epidural fat and the L7-S1 intervertebral disc was hypointense. The cauda equina was compressed and elevated at the level of sacral region. We diagnosed this dog as lumbosacral stenosis at L7-S1 lesion.Dog 3: The clinical sign in this dog was decreased tail tone and weakness of the hind limbs, especially left side. The sagittal T1-weighted image (Fig. 3) showed that L7 vertebral body was destroyed and the L7-S1 intervertebral disc was hypointense and the osteophyte at ventral side of the L7 vertebral body was slightly hypointense. We diagnosed that the cauda equina was compressed by means of the destroyed L7 vertebral body and osteophyte.Hathcock et al. [3] showed that it was difficult to diagnose the cauda equina syndrome, because survey radiography or myelography has not been able to reveal the cauda equina lesion. In epidulography or discography [11], the result was sometimes false as the contrast medium leaked to arachinoid space and after examination, some animals rarely showed back pain. The advantage of MRI was that it was able to show, without the use of contrast medium, the * CORRESPONDENCE TO: TAURA, Y., Department of Veterinary Hospital, Faculty of Agriculture, Yamaguchi University, 1677-1 Ooaza Yoshida, Yamaguchi 753-8515, Japan. Cauda equina syndrome causes compression, displacement, and disorder of nerve roots in lumbosacral region [6,10,12]. Until now several examinations are used to confirm a diagnosis of cauda equina syndrome [1-4, 6, 11]. However, it is difficult to make a definite diagnosis. Recently, MRI as a diagnosic tool has come into wide use in veterinary practice [5,[7][8][9]13]. Because of high resolution of MRI, it is possible to get clear images of cauda equina [2,4]. The purpose of present study was to survey anatomical change of cauda equina lesion in three dogs of different breeds and t...

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Magnetic resonance imaging in the diagnosis and surgical management of sacral osteochondrosis in a mastiff dog

“…In the present case, mri was used to characterise the degree of compression of the cauda equina and the extent of the fibrous tissue associated with the lesion. The technique makes it possible to visualise the nerve roots, the intervertebral discs and the ligaments directly (de Haan and others 1993, Kraft and others 1998, Ramirez and Thrall 1998, Taga and others 1998), and it provides soft tissue contrast that is superior to computed tomography and does not require the use of ionising radiation (Ramirez and Thrall 1998). However, it is expensive and not widely available.…”

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